assessment of cardioversion using transesophageal echocardiography ii (acute ii)

Conditions: Atrial Fibrillation

Summary: specific aim: to test the safety and feasibility of using low molecular weight heparin (lmwh, enoxaparin sodium; lovenox, sanofi-aventis) in lieu of unfractionated heparin (ufh) as antithrombotic therapy for patients in atrial fibrillation undergoing transesophageal echocardiography (tee) guided chemical or electrical cardioversion to sinus rhythm. hypothesis: early cardioversion from atrial fibrillation can be safely performed using a short-term anticoagulation strategy of low molecular weight heparin (lovenox, sanofi-aventis) compared to unfractionated heparin, accompanied by a tee examination prior to cardioversion. the use of lmwh with tee will result in a safe, cost-effective, and possible efficacious approach to cardioversion of atrial fibrillation compared to ufh with tee.


Eligibility criteria:
inclusion criteria: * patients with chronic or paroxysmal atrial fibrillation of \> 2 days duration who are candidates for early chemical or electrical cardioversion * patients with atrial flutter with a documented history (electrocardiography) of atrial fibrillation * males and females 18 years of age or older * patients have available results of routine clinical labs for standard clinical chemistry and complete blood count within the previous 14 days exclusion criteria: * an inr \> 1.4 in patients who have received warfarin prior to enrollment. * use of iv heparin for more than 72 hours immediately prior to randomization. * patients with contraindications to tee, such as dysphagia, or esophageal strictures. * patients who will need anticoagulation discontinued because of elective intervening procedure, such as cardiac catheterization or surgery. * patients with contraindications to warfarin or heparin * patients who require concomitant therapy during the study period with any drug known to affect coagulation or platelet function (i.e. asa, nsaid, antiplatelet drugs) * women of childbearing potential, unless pregnancy can be excluded by medical history incompatible with pregnancy or by serum or urine beta hcg levels. * patients who are hemodynamically unstable and thus may require immediate cardioversion. * weight less than 40 kg (88 pounds) or more than 125 kg (275 pounds) * history of gastrointestinal bleeding disorder and/or endoscopically verified ulcer disease within the last year * history of intracranial or retinal bleeding, or other known disorders with an increased risk of bleeding * ischemic stroke in the previous three months * uncontrolled hypertension (systolic blood pressure greater than 180 mm hg or diastolic blood pressure greater than 100 mm hg) * malignancy currently under active treatment, including melanoma * patients with renal insufficiency (creatinine \> 2.0 mg/dl) or are renal transplant subjects * patients with anemia (hgb less than 10 gm/dl) * patients with thrombocytopenia (platelet count less than 100 x 10\^9/l) * positive fecal hemoglobin test * life expectancy of less than 6 months * history of drug and/or alcohol abuse within the last two years * patients unable or unwilling to give informed consent * patients unable or unwilling to return for follow-up * prisoners or wards of the state * patients with psychological problems that may decrease compliance with the protocol * not willing to complete the quality of life questionnaires x 3 * participating in another clinical trial and/or taking an investigational medication in the past 30 days * patient language, learning skills, or home environment unconducive to self-management

Keywords: atrial fibrillation atrial thrombus cardioversion enoxaparin low molecular weight heparin transesophageal echocardiography